A MELBOURNE couple endured 10 years of utter heartbreak — unsuccessful IVF attempts, miscarriages, and the devastating death of their precious 11-day-old son — before welcoming a medical marvel believed to be Australia’s first “twiblings”.

Twiblings is a term used in IVF circles to describe two children conceived in-vitro at roughly the same time from sperm and eggs from the same people, but carried by two different surrogates.

It became a living, breathing reality for Melbourne couple Danielle and Sean just over a year ago, in the form of babies Ethan and Ava.

Danielle and Sean’s parallel surrogate pregnancy story was not without its final trials, with Ava’s dramatic entry into the world documented on factual reality show, The Embassy, on Wednesday night.

The birth of baby Ava, in Thailand to a commercial Thai surrogate, came four weeks after her “twibling” brother Ethan was born in Melbourne, carried by a voluntary surrogate — Danielle’s best friend.

With Danielle at home caring for Ethan, Sean had travelled to Thailand for Ava’s birth, and to complete the birth certificate, passport and citizenship formalities to allow him to bring her home to Australia.

Things took a terrifying turn when three-day-old Ava was diagnosed with three holes in her heart, leaving her in danger of heart failure.

Worrying vigil: Sean feeds sick Ava in hospital as they wait for her to be well enough to get to Australia. Picture: Supplied by Channel Nine

A frantic Sean turned to Australian embassy staff to get his Ava home to Australia in time for a vital cardiologist appointment.

The reunion was the final step in a 10-year battle for IT software specialist Sean and special needs teacher Danielle, who spent hundreds of thousands of dollars and endured almost unimaginable loss along the way.

After seemingly countless fruitless attempts at IVF they finally fell pregnant, and three years ago welcomed a son, Aidan. But they were left utterly devastated when Aidan developed a bowel infection, and they had to make the heartbreaking decision to turn off Aidan’s life support when he was just 11 days old.

The hits kept coming when Danielle was told she would never carry a baby to full term.

With surrogacy the only option, and just two viable embryos remaining after more unsuccessful IVF implant attempts, the couple took one last throw of the dice.

With the odds of success running at less than 10 per cent, one embryo was implanted into their friend, the other into a Thai woman willing to be their commercial surrogate, both with success.

Now, more than a year after welcoming Ethan and Ava, the couple have drawn a curtain over their private lives as their children grow, but their battle — and the joy when it was over, remains a fond memory for Australian embassy staffer Trudy McGowan.

“To see him (Sean) so distraught, and who wouldn’t be when a baby is so sick, and then hear about all that had led up to tiny Ava, how could your heart not go out? They’d been through such a difficult time,” McGowan said.

“At the time, as it unfolded in Thailand, I was just focused on helping Sean and Ava. It wasn’t until I saw the footage of Ava and Danielle meeting for the first time at the airport that the emotion hit me. ”

And it was lucky timing for Danielle and Sean. Thai authorities have since banned commercial surrogacy in Thailand.

The Embassy is on Channel 9 at 8.30pm Wednesday.

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